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P Hartge

Publications and source records attributed to P Hartge.

At least 55 records · Page 3Linked to original sources

Attributable risk: advantages of a broad definition of exposure.

Classification of exposure into two levels--one consisting exclusively of unexposed individuals and the other consisting of exposed and perhaps unexposed ones--yields an unbiased estimate of attributable risk when misclassification is nondifferential. The authors advocate, therefore, the use of a broad definition of exposure when estimating attributable risk. Based on this idea, they justify a simple and robust method for estimating the overall attributable risk from several exposures that is based on a division of subjects into two groups, a baseline consisting of those unexposed to all exposures and everyone else.

Asbestos↗

Associations between bladder cancer risk factors and tumor stage and grade at diagnosis.

Using data on 1,860 bladder cancer cases and 3,934 population-based controls from the National Bladder Cancer Study, we examined associations between suspected bladder cancer risk factors and tumor stage and grade. Employment in a high-risk occupation was associated with the entire clinical spectrum of bladder cancer rather than a particular tumor stage or grade. For example, relative risks (RR) were similar for noninvasive and invasive disease (1.5 and 1.6, respectively). Cigarette smoking also increased risk of the entire clinical spectrum of bladder cancer, but the more advanced the stage, the stronger the effect. For example, relative risks of noninvasive and invasive bladder cancer for current heavy smokers were 3.0 and 5.2, respectively. Cigarette smoking was associated with higher risk of low-grade than high-grade tumors, once stage of disease was taken into account. Compared with whites, nonwhites were at a lower risk of noninvasive bladder cancer (RR = 0.4) but at similar risk of invasive bladder cancer (RR = 1.1), a pattern indicating racial differences in health practices related to bladder cancer detection. History of urinary tract infections and bladder stones was associated with increasing relative risks for advanced tumor stage. Heavy artificial sweetener use was associated with higher-grade, poorly differentiated tumors. Coffee consumption and family history of bladder cancer were not consistently associated with tumor stage or grade. Overall, different clinical presentations of bladder cancer share most suspected bladder cancer risk factors, including employment in a high-risk occupation and cigarette smoking.

Adult↗

Hodgkin's and non-Hodgkin's lymphomas.

Incidence of HD varies from about 0.5 per 100,000 person-years in parts of Asia to over 3 in parts of North America. In recent decades, many registries have reported slightly declining age adjusted incidence among men and women. Some lymphomas previously diagnosed as HD now would be classified as NHL, but this shift does not explain all of the decline. When analysed by age group, incidence has decreased substantially at older ages, whereas increases have been reported among young adults in some industrial countries. Less developed countries continue to show high rates in childhood. Hodgkin's disease of the nodular sclerosis subtype has increased over time, whereas HD of mixed cellularity has declined. Improved therapy for HD has led to sharply declining mortality rates, but further understanding of the role of EBV and other possible causal agents should afford opportunities for prevention. Non-Hodgkin's lymphoma stands out from most other malignancies because incidence and mortality rates have risen dramatically, steadily and almost universally during the past few decades. Incidence overall has been rising 3-4% per year. No sudden rise has occurred in specific birth cohorts or calendar year of diagnosis, although incidence rates have increased more steeply at older ages. Diagnosis of NHL has improved with time, perhaps beyond the ways considered herein, but has it improved so much more than diagnosis of other malignancies, and roughly simultaneously around the world? Although it appears that diagnostic improvements are partly responsible for the upward trend, it is likely that aetiological factors are playing an important part. Infections with HIV have started to inflate NHL incidence rates further but cannot account for the striking trend already under way for several decades. Clues should be vigorously pursued to determine the role of other known viruses, immunosuppressive states, herbicides and other chemicals in the environment, and commercial products such as hair dyes. To clarify reasons for the upward trends and to take preventive action will require a better understanding of the origins of the lymphomas through epidemiological research, including interdisciplinary approaches that can identify new viruses, host-environmental interactions and lifestyle and other exposures that alter susceptibility.

Adolescent↗

Occupation and ovarian cancer: a case-control study in the Washington, DC, metropolitan area, 1978-1981.

Ovarian cancer risk factors may be genetic, reproductive, or hormonal in nature. Occupational exposure to talc and other carcinogenic substances has not been studied in relation to ovarian cancer risk. We therefore examined the job histories of 296 women aged 20 to 79 who were diagnosed with epithelial ovarian cancer in the Washington, DC area in 1978 to 1981, comparing them to 343 hospital controls, matched for age and race. A blind exposure assessment, evaluating each job/industry combination for potential exposure to talc, ionizing radiation, polycyclic aromatic hydrocarbons, and solvents was conducted by an industrial hygienist blind to case-control status. Women exposed to talc had a relative risk of ovarian cancer below the null, but the confidence interval was wide and there was no evidence of a trend. Women exposed to polycyclic aromatic hydrocarbons had an elevated relative risk, also with a wide confidence interval and no evidence of a trend with duration.

Adult↗

Rates and risks of ovarian cancer in subgroups of white women in the United States. The Collaborative Ovarian Cancer Group.

OBJECTIVE: To provide estimates of the age-adjusted incidence and lifetime risk of ovarian cancer in subgroups of women defined by key risk factors. METHODS: We combined data from seven case-control studies (1122 cases and 5359 controls) with Surveillance, Epidemiology, and End Results incidence data to estimate the incidence rate and probability of developing ovarian cancer within subgroups of women defined according to the three major known risk factors: a history of ovarian cancer in the mother or sister, years of oral contraceptive (OC) use, and number of term pregnancies. RESULTS: Among women with no family history of ovarian cancer, the risk at age 65 varied from 0.3% among those who had had three or more term pregnancies and 4 or more years of OC use, to 1.6% among nulliparous women with no OC use. Among women with a positive family history, the risk of developing ovarian cancer by age 65 was estimated as 4.4% and the lifetime risk as 9.4%. The data were too sparse to estimate the risks associated with OC use and pregnancy among women with a positive family history. CONCLUSIONS: The risk of developing ovarian cancer within the total population of white women can be divided informatively into component risks within subpopulations. At birth, the estimated risk of developing ovarian cancer before age 65 for the total population is 0.8%, but the component risks vary 15-fold, from 0.3 to 4.4%.

Adult↗

Role of HTLV-I in development of non-Hodgkin lymphoma in Jamaica and Trinidad and Tobago. The HTLV Lymphoma Study Group.

Human T-cell lymphotropic virus type I (HTLV-I) has been implicated in the aetiology of adult T-cell leukaemia/lymphoma in Japan and elsewhere, particularly the Caribbean. We have carried out parallel case-control studies in Jamaica and in Trinidad and Tobago to quantify the role of HTLV-I in the development of non-Hodgkin lymphoma (NHL). 135 cases of NHL were enrolled in Jamaica and 104 in Trinidad and Tobago. Controls were selected from patients treated in the same wards or clinics at the same time as the cases. Overall, patients with NHL were 10 times more likely than were controls to be seropositive for HTLV-I (Jamaica odds ratio 10.3 [95% CI 6.0-18.0], Trinidad and Tobago 14.4 [7.6-27.2]). In both countries the association between NHL and HTLV-I was greatest for T-cell lymphomas (18.3 [9.5-35.6] and 63.3 [25-167]). Among T-cell lymphomas especially, there was no significant difference between men and women in the association between NHL and HTLV-I, but there was a significant inverse relation between age and likelihood of HTLV-I seropositivity. B-cell lymphomas were predominant in the older age groups and were not associated with HTLV-I seropositivity. These findings are consistent with the hypothesis that early life exposure to HTLV-I is important for risk of subsequent ATL. Prevention of vertical transmission of HTLV-I could reduce by 70-80% cases of NHL in people under 60 years in this region.

Adult↗

Validation studies using an alloyed gold standard.

A key assumption made when using a validation study to correct an estimate of relative risk for bias due to misclassification or measurement error is that the available measure, known to have error but nonetheless used routinely in the main study, is compared to a gold standard measured without error. In most epidemiologic applications, the putative gold standard is in fact measured with error. The effect of the violation of the assumption on the corrected estimate depends on the magnitudes of the errors in the two measures and on their correlation. In particular, when the errors are negatively correlated, independent, or weakly positively correlated, the corrected estimate will tend to overcorrect beyond the true value.

Bias↗

Race and sex differences in associations of vegetables, fruits, and carotenoids with lung cancer risk in New Jersey (United States).

We used data from a case-control study conducted in New Jersey between 1980 and 1983 to evaluate race and sex differences in associations of vegetable, fruit, and carotenoid consumption with lung cancer. Cases included 736 White males, 860 White females, 269 Black males, and 86 Black females with incident, histologically confirmed, primary cancer of the trachea, bronchus, or lung. Controls were identified through drivers' license and Health Care Financing Administration files and included 548 White males, 473 White females, 170 Black males, and 47 Black females. Usual intakes of vegetables (predominantly yellow/green) and fruit (predominantly yellow/orange) as well as other food sources of carotenoids were ascertained by a food frequency questionnaire. White females showed significant inverse associations of lung cancer with vegetables, fruit, and carotenoids. White males showed nonsignificant inverse associations with vegetables and carotenoids, and Black females just with vegetables. No inverse associations were found for Black males. Vegetable consumption was associated with risk of all histologic types of lung cancer, but the pattern of increasing risk with decreasing intake was limited to smokers. We infer that consumption of yellow/green vegetables and carotenoids may confer protection from lung cancer to White male and White female smokers. Further studies are needed to clarify the effect in Blacks.

Black or African American↗

Smoking and bladder cancer risk in blacks and whites in the United States.

A population-based case-control study of bladder cancer (2,982 cases and 5,782 controls) conducted in 10 areas of the United States examined the effect of smoking as a risk factor among Blacks and Whites, after adjustment for occupation and other potential confounders. Although the overall risk for smoking was slightly higher in Blacks than Whites (relative risk = 2.7 and 2.2, respectively), this difference was not statistically significant. Estimation of risk by dose and currency of exposure revealed no consistent racial disparities in smoking-related risks. Race-specific, attributable risk estimates indicated that nearly half of bladder cancers among both Blacks and Whites could have been prevented by elimination of smoking.

Adult↗

Familial and cutaneous features of dysplastic nevi: a case-control study.

BACKGROUND: Although dysplastic nevi are an important risk factor for melanoma, little is understood about the epidemiology of these nevi. To further characterize some of the correlates of dysplastic nevi, we reexamined patients from one of the original prevalence reports and their first-degree relatives. OBJECTIVE: Our purpose was to characterize the prevalence and correlates of dysplastic nevi. METHODS: We studied 25 persons originally diagnosed with dysplastic nevi in 1980 and 1981, 28 controls stratified by age, sex, race, and date of initial examination, and all willing first-degree relatives of both patients (n = 78) and control subjects (n = 76). Each study subject underwent a full skin examination and biopsy of nevi suspected of being dysplastic nevi, if willing. RESULTS: Eighty percent of the case kindreds were multiplex (2 members or more affected) for dysplastic nevi; the relative risk of having dysplastic nevi was 7.2 (95% confidence interval 2.1 to 24) if one or more relatives had dysplastic nevi. Three of the cases (12%) in multiplex families also had a first-degree relative with melanoma. Cases and relatives with dysplastic nevi of both patients and control subjects tended to have increased numbers of nevi. The risk of having dysplastic nevi rose 99-fold in persons with more than five nevi 4 mm or larger and/or scars on their back (p < 0.001). CONCLUSION: These data support the hypothesis that family members of unselected persons with dysplastic nevi are likely to have dysplastic nevi and may be at increased risk of melanoma.

Adult↗

The inheritance pattern of dysplastic naevi in families of dysplastic naevus patients.

Dysplastic naevi (DN) are the major precursor lesions of malignant melanoma, yet the presumed mode of inheritance or genetic aetiology of DN remains controversial. The inheritance pattern of DN in families from a randomly selected population of 26 dysplastic naevus patients was investigated by estimating the segregation ratio in families ascertained through an offspring with DN (incomplete ascertainment). For families ascertained through a parent with DN (complete ascertainment) the transmission pattern was examined by comparing the observed number of affected offspring to the expected number using a chi 2 goodness-of-fit test. Results from the chi 2 tests and the estimated segregation ratio of 0.52 (95% confidence interval: 0.31, 0.73) suggest that the inheritance pattern for dysplastic naevi in these families is consistent with autosomal dominant transmission, although the present study was limited because of a small sample size. The findings, therefore, need to be confirmed by a much larger study that is able to test more rigorously specific genetic hypotheses.

Dysplastic Nevus Syndrome↗

Determinants of the geographic variation of invasive cervical cancer in Costa Rica.

The incidence of cervical cancer in Costa Rica is about twice as high in the coastal regions as in the interior. To study these regional variations, we used data from a 1986-1987 case-control study of 192 Costa Rican women with invasive cervical cancer and 372 controls. Risk factors identified included the following: The study participant's (1) number of sexual partners, (2) age at first sexual intercourse, (3) number of live births, (4) presence of type 16/18 human papillomavirus (HPV) DNA, (5) venereal disease (VD) history, (6) Pap smear history, and (7) socioeconomic status. The adjusted relative risks (RR) and 95% confidence intervals (CI) for each of these risk factors were as follows: (1) > or = 4 vs. 1 sexual partner: RR = 2.0, 95% CI = 1.1-3.5; (2) age of initiation < or = 15 vs. > or = 18 years: RR = 1.5, 95% CI = 0.9-2.5; (3) > or = 6 vs. < or = 1 live birth: RR = 1.7, 95% CI = 0.7-3.9; (4) HPV 16/18 DNA in cervix: RR = 2.8, 95% CI = 1.9-4.2; (5) VD history: RR = 2.2, 95% CI = 1.2-4.0; (6) no Pap smear: RR = 2.4, 95% CI = 1.5-3.8; and (7) low socioeconomic status: RR = 2.0, 95% CI = 1.2-3.2. The population-attributable risks related to HPV detection, four or more sexual partners, six or more live births, no prior Pap smear, and low socioeconomic status were 39%, 38%, 29%, 23%, and 22%, respectively. Several of the sexual and reproductive risk factors were relatively more prevalent in the high-risk region, but Pap screening and detection of HPV were equally prevalent in the high-risk and low-risk regions. Though differences in screening quality (laboratory and follow-up) may have been involved, we conclude that the observed regional differences reflect behavioral more than screening differences. This suggests that screening programs should be more aggressive in the high-risk area, given the more frequent occurrence of the disease there. Failure to detect a higher prevalence of HPV in the high-risk region could reflect weaknesses in the in situ hybridization test employed. Alternatively, cofactors may have to be present in order for HPV to exert its role in cervical carcinogenesis.

Adult↗

Age at onset for familial epithelial ovarian cancer.

OBJECTIVE: To provide age-specific risks for ovarian cancer for relatives of ovarian cancer case patients. To characterize the age at onset for ovarian cancer for women with a single relative vs several relatives affected with ovarian cancer. DESIGN: Three previous studies were reexamined. The cumulative probability of ovarian cancer in first-degree relatives of women with histologically confirmed epithelial ovarian cancer and matched control subjects who participated in the Cancer and Steroid Hormone (CASH) Study was determined. The age of onset of ovarian cancer in women with and without relatives with ovarian cancer in a Washington, DC, case-control study was contrasted with that of women with at least two first-degree relatives studied at the National Cancer Institute (NCI). RESULTS: The CASH Study data showed that first-degree relatives of women with ovarian cancer had an increased risk for ovarian cancer, especially at older ages, when compared with relatives of control subjects. However, the median age at onset was the same among women in the Washington, DC, study with and without an affected relative. Among the women with an extensive family history of ovarian cancer studied at the NCI, the age at onset was considerably younger (47 years) than is typical for this disease (59 years). Of these, 17% had been diagnosed as having primary ovarian cancer by age 40 years. CONCLUSIONS: Women who have one first-degree relative affected by ovarian cancer are at greater risk for ovarian cancer but not at an age earlier than the general population. The small proportion of women who have several affected relatives are, however, at a greater risk of early onset of ovarian cancer. Prophylactic oophorectomy may be reasonable for these women.

Adult↗

Quantification of the impact of known risk factors on time trends in non-Hodgkin's lymphoma incidence.

The incidence of non-Hodgkin's lymphoma among white men in the United States was measured as 6.9/100,000 person-years in 1947-1950 and as 17.4 in 1984-1988. We have estimated how much the known and suspected diagnostic and risk factors might have contributed to this apparent increase of 152%. Firm conclusions cannot be drawn without more data on risk and changes in prevalence, but a reasonable range of impacts can be constructed. After accounting for the likely effects of misdiagnosis of Hodgkin's disease as non-Hodgkin's lymphoma, of the acceptance of new entities of non-Hodgkin's lymphoma, of familial factors, of human immunodeficiency virus and other immunosuppressive conditions or drugs, and of occupation, we estimate that the percentage increase in incidence was still 80% among all males and 42% among those aged 0-64. An agent carrying a relative risk of 2.0 rising in prevalence from 0 to 42% would account for the latter rise. Diet, hair dyes, and general environmental exposures to pesticides may be contributing, but currently estimated risks and changes in exposure levels do not appear large enough to account for the residual rise. Among men aged 75-84, some of the residual rise of 109% probably is diagnostic, but only further research will clarify the issue.

Humans↗

Risk factors for epithelial ovarian cancer in Beijing, China.

A study in Beijing, China of 112 pathologically confirmed epithelial ovarian cancer cases and 224 age-matched community controls enabled evaluation of risk in relation to reproductive, medical, familial, and selected lifestyle factors. An inverse relationship was observed between the number of full-term pregnancies and ovarian cancer risk. Compared to nulliparous women, subjects with one, two, or three full-term pregnancies were at 50%, 70%, or 90% reduced risks, respectively (P for trend less than 0.01). A positive correlation was found between the number of ovulatory years and risk, with a 2.6-fold increased risk for women with 30 or more compared to less than 10 ovulatory years (P for trend less than 0.01). Infertility, as estimated in various ways, was also found to be an important risk factor. When parity was taken into account, age at first pregnancy was not related to ovarian cancer risk. No protective effect was associated with mumps virus infection. In contrast, risk increased significantly as serum mumps virus antibody titres increased (P for trend less than 0.01). An elevated risk was found in women with a history of long-term (greater than 3 months) application of talc-containing dusting powder to the lower abdomen and perineum (Relative risk 3.9, 95% confidence interval: 0.9-10.63). These findings suggest that Chinese women have risk factors similar to those of occidental women.

Carcinoma↗

Epidemiology of bladder cancer.

Approximately 49,000 persons in the United States develop bladder cancer each year, and about 9700 die of it. White men face a lifetime risk of almost 3%; white women and black men face a risk of about 1%, and black women, about 0.5%. Cigarette smoking is accepted widely as a cause of bladder cancer. Smoking accounts for about half of bladder cancer diagnosed among men and about one third of that among women. Moderate to heavy smokers typically show a two to five fold risk of bladder cancer, compared with persons who never smoked. When cigarette smokers quit smoking, their bladder cancer risk falls measurably within 2 to 4 years, but probably does not continue to decline with increasing years since quitting and does not appear to return to the baseline level of nonsmokers. Occupational exposure to certain aromatic amines causes human bladder cancer. Clear evidence of bladder cancer risk also is apparent for a small number of occupational groups: dye workers, rubber workers, leather workers, painters, truck drivers, and aluminum workers. Many other occupational groups have been reported to have increased bladder cancer risk, but evidence for these is not as strong. Coffee drinking has been studied extensively as a potential risk factor, but the inconsistency of the observed associations suggests that the relationship is either quite weak, noncausal, or dependent in a complex way on unmeasured factors. Artificial sweeteners confer little or no excess bladder cancer risk. Alcohol consumption apparently does not affect risk either. Consumption of fruits, vegetables, and foods high in vitamin A have been suggested as possible protective factors; consumption of high-fat foods, pork, and beef have been suggested as possible risk factors. Further epidemiologic research is needed to elucidate the role of diet in human bladder carcinogenesis. Less common risk factors for bladder cancer include ionizing radiation, cyclophosphamide use, and abuse of phenacetin-containing analgesics. Schistosomiasis infection may contribute substantially to the bladder cancer burden in Egypt and elsewhere, though not in the United States.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗